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<body>

    <div id="d">123</div>
    <div class="c">456</div>
    <div class="c" id="d">789</div><br /><br />

    <div>s1</div>
    <div class="c">s2</div><br /><br />
    
    <div class="d">s5</div>
    <div class="c d">s6</div><br /><br />

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